Mercedes-Benz Ponton Radios

The radio sets originally supplied with the Mercedes-Benz
Pontons are, like the cars themselves, of another age. The vacuum tubes need
to warm up before the sound begins radiating from the speaker. They are
prone to needing repeated adjustments, yet the audio quality is warm and
inviting. There is something about sitting in a Ponton at night with the radio on,
and hearing the barely audible buzz from the power supply that makes one believe
if they were to tune the dial to the right frequency, they would hear voices
and music from the past. - Jeff Miller / April 5, 2002

Manufacturers / Technology

Becker and Telefunken were approved suppliers of Mercedes-Benz radios,
and the Becker "Mexico" was the top of the line for the Ponton
passenger cars of the 1953-1962 period (Service
Manual Model 190 / Job No. 82-20). In addition to the radios made by
Becker and Telefunken, the factory also approved the subsequent dealership installation
of radios made by Blaupunkt and Philips. Even though these other
fine German radio manufacturers offered special installation kits, the
Mercedes-Benz price lists usually came only with the footnote that "other
makes of radio (in addition to Becker and Telefunken) can only be retrofitted at sales and
service outlets or authorized agents." It is interesting to note
that the radio was typically the most expensive option on the car. In Europe, the FM
radio band was 87.5 MHz - 100 MHz up until the mid 1960s when it was expanded to 108
MHz. I have been led to understand that the French police were using the frequencies above 100 MHz until the
mid 1960s, thus preventing Germany and other European countries from including those
frequencies in their public FM broadcast spectrum. Increasing the FM frequency range to 108
MHz on the early radios is possible, but the lower frequencies will be lost.
These were heavy vacuum tube radios which had equally massive power supplies
mounted separately under the dash. Also available was a Becker
"Reims" adapter for short-wave reception which was attached to the lower
portion of the radio under the speaker cabinet.
In Europe, parts of Asia and North Africa the long-wave band (150-280 KHz) is used for
broadcasting. Radio sets from this part of the world have the LW (long-wave, LF)
and the BC (AM or MW) band and the short-wave band in use. The long-wave band is very
interesting because long distance reception during the day and DX (very long distance at night) is
possible. In America and Australia the long-wave broadcast band was not in
widespread use so the car radios built for export did not include it. All of
these radios can be used on 6V or 12V by changing the frequency modulator (also known
as: "chopper", "buzzer", or "vibrator") and some
jumpers on the old G type transformer and by a switch in the later transistor powered
supplies. The "vibrator" converts the low (12V) DC car battery
voltage to "pulsating DC" which can then drive the primary of a
step-up transformer to provide high AC voltage which is then rectified to
provide high voltage DC to supply the B+ for the valves (vacuum tubes) which
require higher voltage than the car battery could otherwise provide.
Around 1958 as technology advanced, the heavy power supplies were first replaced
by smaller solid-state transistorized units. In the early 1960s the
electronic parts got small enough that the power supply was being included with
the tuner and amplifier as a self-contained unit.
By 1962 tubes finally disappeared from automobile radio design altogether.

Originality

The faceplates on these radios are of different heights and the
styling can vary slightly between models with some having a different curve
radius at the corners. The fragile Bakelite speaker cabinets
used in the sedans with the Blaupunkt and Becker radios are also different from each
other. The convertibles and coupés used a wooden speaker cabinet.
The barrels of the early radio knobs were metal with a set screw to lock them in
place on the shafts of the on/off switch and the tuning dial. The knurled thumbwheel portion of
the knob was chromed and finished with a brown Bakelite cap. After 1959,
certain radios had black rubberized tuning knobs to match the rest of the dashboard
layout. These subtle differences can offer challenges to the Ponton owner
who wants to fill the gaping hole in the dashboard with the correct period
radio seen at a swap meet or an on-line auction. The vehicle's data
card lists option codes for original factory installed equipment and can
help determine the specific radio that came with the car when it was delivered
new.

Sales / Service / Repair / Schematics

Service and repair is generally not a problem
because the vacuum tubes and other electrical components such as resistors, capacitors
(condensers) are still available. However; certain parts such as
switches must be obtained from donor radios. For more information regarding
parts availability and repair see the Links page.

Sams Photofact Sets (schematics and layout photos) are available for some
Blaupunkt and Becker models. See caveat about
buying photo-copies of schematics on-line versus making photocopies at your
local Public Library.

Sam's Photofact Sets and Rider Technical Manuals are Available at the Public Library

Before you pay top price (eBay, on-line vendors, etc.) for photocopies of
Sam's Photofact Sets, or Rider Technical Manuals, check your Public
Library first. Many libraries still have these documents readily available
and will let you make copies for a nominal fee. A photocopy of a typical
twelve-page Sam's Photofact Set will cost about $1.50 at your Public Library.

In the days of "point-click-pay" it is easy, and quite possible to
over-pay for low quality, multiple-generation photocopies. It may not
be obvious what the quality is like until you receive the package.
Remember, the documents can be copied cheaply, quickly and accurately
by yourself at the library.

Note that some websites have generously provided free on-line .pdf file
schematics, but they have occasionally been found to be labeled
incorrectly. This only becomes obvious when the schematics are
used to create "shopping lists" for new components, or when the circuit
troubleshooting begins. If the component values found in the radio
are nowhere near the values shown in the .pdf files, then some
investigation work needs to be done. Again, take a trip to your local
Public Library and look up the Sam's Photofact Set or Rider Technical
Manual for your radio, if available. These companies did not make
technical documents for each and every radio ever produced.

The librarian will be happy to show you where they store the
Sam's Photofact Sets or other technical data sets. By making the
copies yourself, you verify the schematics are correct for your
radio, and ensure the quality of the photocopy is high. Take the
money you save and put it towards the radio restoration!

If you have schematic data for additional Mercedes-Benz Ponton radios, please
contact the editor.

Ramzi writes, "This is the Becker Mexico AM/FM automatic signal searching
radio installed in my 1961 180b Ponton sedan.
One of the switches next to the search bar adjusts the sensitivity of the search,
which means it can stop on all stations (more sensitive), or only the ones with strong signals
(less sensitive).
The other switch is to adjust the bass and treble. It will increase the treble
and decrease the bass and vice-versa. This radio was in a Type 180 sedan
that was
brought to Lebanon in the late 1960s as a parts car. I bought it from an old
guy who kept it for about 30 years. It was not working, but it has been repaired.
Note that the tuning knobs are the later rubberized style."

Update / November 11, 2014: Ramzi's Becker Mexico
developed a problem. All was working fine except that the "wonder bar" did
not detect any stations. It kept going to the right, then rewinding, then
back to the right, and never stopped until the radio was turned off.

Senen Racki wrote..."The Becker Mexico signal seeker works by
loading a spring by way of actuating a strong electromagnet at the push of
the "wonder bar." That energy is then released slowly via a clockwork mechanism
that moves a series of rods through a set of inductors, thereby changing the
tuning. When a strong signal is detected, an electromagnet is de-energized and releases a locking arm onto a paddle wheel to stop the clock mechanism."

"Since the radio seems to work normally otherwise,
the signal strength isn't in question, so the parts to look at are the
electromagnet, locking arm, paddle wheel, and associated circuitry. The
photo clearly shows these parts. If all else fails, contact
Becker Autosound. They will surely have a
solution for you."

Telefunken radio in a Mercedes-Benz Ponton (Type 180/190 or 219). Note
the speaker grille in the Bakelite surround, directly below the radio. There appears
to be a second speaker mounted under the dash. In fact, this
configuration has no speaker behind the Bakelite grille. The only
speaker is part of the power supply, which is the unit mounted
under the dash.

Telefunken radio from a 1957 Type 190 sedan (European
specification).

Telefunken is the abbreviation or trade name of the large German wireless
(radio) concern, the full name of which is Gesellschaft für drahtlose Telegraphie m.b.H. The name is composed of the words "Funken," which is the German plural of "Funk", a spark, and "Tele," which has the same meaning as the English, namely "afar" (from the Greek
tele).

The speaker grille below this radio is empty. The only
speaker in this configuration is part of the power supply, mounted below
the dash.

Note

Gary Kuster writes, "My 1957 Mercedes-Benz Type 219 Ponton sedan
(chassis number 105.010-75-02519) has a Telefunken radio with an under-dash speaker and power
supply, as shown in the photos on this page. The Bakelite grill
beneath the radio is empty. The only speaker is located in
the power supply unit, which is mounted below the dash. I am currently restoring this car, and am certain
this aspect was untouched."

Becker "Reims" Short-Wave Radio Adapter

The Becker "Reims" short-wave adapter enabled the Mercedes-Benz
Ponton-era radios to receive short-wave bands. The number of tuning push-buttons and
their band designations ("16" = 16 meter band, for example) varied from model to model.

The Reims unit has the role of converting the AM ("MW" or
"Mittel Welle") radio band into pre-selected SW frequency ranges. My
particular Reims unit (which is not shown in these photos) has the following
push buttons: 0, T1, T2, 49, 31, 25, 19. When the zero button is pushed, the
Reims converter is inactive, and one will be able to tune any station on the AM
band. When any other button is pushed, the Reims converts the AM band into SW.
Then, fine tuning on the SW bands is done by changing the AM dial knob.
This way, one can find SW stations on different meter bands. The different push buttons
on the Reims correspond to different SW bands. Fine tuning allows
reception of all SW stations which were broadcast on designated waves, for example
the Deutsche Welle was on the 49 meter band, and the BBC could be
found on the 19 meter band. I do not know what the T1 and T2 buttons mean.
I was wondering if they must be pushed together with other buttons. I tried that,
but got no results.

The Reims is connected to the radio via the coaxial wire of the antenna.
It is connected between the radio and the antenna. It is powered by the radio's power
supply. Looking at the power supply, one can see a place to connect the Reims to it. When
connected to the power supply, one insures that the Reims will be turned off once the radio is
switched off.

I connected the Becker Europa radio to the Reims short-wave converter, and was
able to tune into some distant SW stations. I believe it was a great invention for
that time, because the listener can shift from one band to the other just by changing the
circuitry, thus picking up a different range of signals through the same antenna.

As my father told me, short-wave was mainly used in Europe and a bit in the
Middle East. But in the 1960s, the AM band (sometimes designated, "MW" or "BC") was
the most popular. My 1961 Type 180b Ponton sedan came with the Reims adapter.
I believe that was a rare option for a car destined to be used in Lebanon. This justifies
the story told to me that my car was purchased from Gargour (Mercedes-Benz agent in
Beirut, still in business today) by the US embassy in Lebanon in 1962. I never
believed that, but now I think he might have had a point because maybe the US embassy employees
would use SW more than ordinary people. Note: When the radio is tuned to the FM,
("LW") the Reims plays absolutely no role.

Becker Reims short-wave adapter and cable to the
power supply under the speaker cabinet of a Mercedes-Benz Ponton
cabriolet. Also note the unusual floor mounted shift lever.

The unit was mounted below the speaker cabinet in front of the power
supply. In the regions where they were intended to be used, both the power
supply and radio tuner have a socket for the Reims short-wave adapter plugs.

Period Speaker Grill Cloth

Similar vintage radio speaker cloth can be obtained from
Becker Autosound. A swatch this size is enough for one radio and costs
about $10.00 (December 2014). See the Links page for their
website.

Hirschmann Automobile Antennae (1960-1961)

Period "Red Tip" (Kofa 200) Hirschmann Antenna

Original "red dot" Hirschmann antenna (model "Kofa 200") for 1950s and 1960s
German vehicles. Hirschmann was the OEM supplier for Mercedes-Benz, Volkswagen and Porsche (Type 356).
These are still available, but expensive. In September 2003, an on-line auction vendor in Germany
set the bidding to begin at $175 USD.